Molluscum contagiosum virus is a human poxvirus that causes lesions that can persist for months to years in the skin of healthy or immunodeficient individuals, particularly children. Infection with this virus is increasing and has become a troublesome complication for adults with AIDS. At present there is no specific preventive or treatment for the disease. All attempts to culture the virus have failed and little is known about it. The object of the project is to analyze the structure of the viral genome and determine its mode of expression and replication. The way in which the virus resists the human immune system is of particular interest. A set of overlapping plasmids containing all but the very ends of the viral genome were sequenced and the data are being assembled. Preliminary analysis indicates that there are about 200 genes of which approximately half are homologous to vaccina and variola virus genes and the other half are unique to molluscum contagiosum virus. Many of the orthopoxvirus genes that are involved in host interactions are not present in molluscum contagiosum virus. Some of the unique molluscum contagiosum virus genes are homologous to eukaryotic genes.